Difference between revisions of "Modified Bessel I"

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$$I_{\nu}(z)=i^{-\nu}J_{\nu}(iz),$$
 
$$I_{\nu}(z)=i^{-\nu}J_{\nu}(iz),$$
 
where $J_{\nu}$ is the [[Bessel J sub nu|Bessel function of the first kind]].
 
where $J_{\nu}$ is the [[Bessel J sub nu|Bessel function of the first kind]].
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 +
=Properties=
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<div class="toccolours mw-collapsible mw-collapsed">
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<strong>Proposition:</strong> The following formula holds:
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$$I_{-\frac{1}{2}}(z)=\sqrt{\dfrac{2}{\pi z}} \cosh(z).$$
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<div class="mw-collapsible-content">
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<strong>Proof:</strong> █
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</div>
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</div>
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<div class="toccolours mw-collapsible mw-collapsed">
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<strong>Proposition:</strong> The following formula holds:
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$$I_{\frac{1}{2}}(z)=\sqrt{\dfrac{2}{\pi z}}\sinh(z).$$
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<div class="mw-collapsible-content">
 +
<strong>Proof:</strong> █
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</div>
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</div>
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<div class="toccolours mw-collapsible mw-collapsed">
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<strong>Proposition:</strong> The following formula holds:
 +
$$I_{\nu}(z)=\displaystyle\sum_{k=0}^{\infty} J_{\nu+k}(z) \dfrac{z^k}{k!},$$
 +
where $J_{\nu}$ denotes the [[Bessel J sub nu|Bessel function of the first kind]].
 +
<div class="mw-collapsible-content">
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<strong>Proof:</strong> █
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</div>
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</div>

Revision as of 05:27, 16 May 2015

The modified Bessel function of the first kind is defined by $$I_{\nu}(z)=i^{-\nu}J_{\nu}(iz),$$ where $J_{\nu}$ is the Bessel function of the first kind.

Properties

Proposition: The following formula holds: $$I_{-\frac{1}{2}}(z)=\sqrt{\dfrac{2}{\pi z}} \cosh(z).$$

Proof:

Proposition: The following formula holds: $$I_{\frac{1}{2}}(z)=\sqrt{\dfrac{2}{\pi z}}\sinh(z).$$

Proof:

Proposition: The following formula holds: $$I_{\nu}(z)=\displaystyle\sum_{k=0}^{\infty} J_{\nu+k}(z) \dfrac{z^k}{k!},$$ where $J_{\nu}$ denotes the Bessel function of the first kind.

Proof: